It is desirable for insulative articles, such as clothing, bedding, sleeping bags, etc., to be able to retain heat. Traditionally, this goal has been effectuated through the use of feathers (down) in insulation materials. U.S. Pat. No. 6,802,081 teaches of the difficulties in the art relating to the blending of moisture-absorbent/releasable heat-generating fiber with a fiber of another species at a stable blending ratio. U.S. Pat. No. 6,802,081 discloses insulation that includes fibers (e.g., feathers) having a specified air layer of not less than 50 ml per gram. The immobile air layer is imperative, as it serves to retain heat in the insulation.
Notwithstanding previous efforts, a need remains for novel insulation materials that are capable of generating and retaining heat.
While certain aspects of conventional technologies have been discussed to facilitate disclosure of the invention, Applicant in no way disclaims these technical aspects, and it is contemplated that the claimed invention may encompass one or more of the conventional technical aspects discussed herein.
In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was, at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.